The Earth's Shifting Crust by Charles Hapgood - wire of information

THEMOUNTAINS 99
would rise in the crack, and the blocks would sink, until the
cracks weie filled up far enough to establish hydrostatic bal-
ance. But this did not solve the problem; it did not help
because nobody could imagine what could produce the neces-
sary pulling apart of the blocks.
For those who like to see complicated problems made sim-
ple, Mr. Campbell's presentation
of this matter is worth
considering. He suggests that the concept of a great sector
of the crust being stretched, and thereby fractured in in-
numerable places at one time, permits a comparison
to be
made with an ice sheet, which is floating on water, and which
undergoes fracturing. Just as the individual pieces of the ice
floe sink, until they have displaced their weight in water,
and the water rises in the cracks between the pieces, so he
visualizes the behavior of the crust during its displacement
equatorward. He sees this as the explanation of the fact that
invasions of
although the crust is shot through with igneous
all sorts, these are hardly ever known to reach the surface of
the earth. He compares the behavior of the crust during dis-
placement
with the behavior of ice as follows:
... As a matter of fact the lithosphere (or crust) can be likened to
ice floating on water, a solid and lighter form of a substance floating
in a liquid and heavier form of a similar substance. The solid and
lighter substance sinks in the heavier and liquid substance until it
displaces its own weight in the heavier and liquid substance and then
floats with its surplus bulk above the surface of the heavier liquid,
which in the case of ice would be one tenth of its bulk. To put it
another way, if you were out on a lake where the ice was ten inches
thick, and you were to bore a hole through the ice to the water, the
water would rise in the hole to within one inch of the surface of the
ice and remain there. Now, that is exactly what happens to the litho-
sphere. It sinks into the asthenosphere (or subcrustal layer)
until it
displaces its own weight of the substance of the asthenosphere and a
state of is equilibrium reached. That will bring the substance of the
asthenosphere far up into the lithosphere, wherever it finds an opening
or a fault that reaches all the way to the bottom of the litho-
sphere (66).
Purely for purposes of illustration, and not as an accurate